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Re: Please remind me!
From: Flint Weller <firstname.lastname@example.org>
> Someone asked me why, "the lizard hipped dinosaurs are said to have
> birdlike hips". You know, I understood this reasoning once, but after
> looking over a few texts, I have something incomplete.
Simply put the pelvic bones of ornithischian dinosaurs *superficially*
resemble those of birds.
In birds the pubic bone is rotated to a position next to the ?ischium.
In bird-hipped dinosaurs the pubis has a posterior process next to
the ischium, and a small forward process.
> Does it have
> something to do with similar muscle attachments?
It has been suggested that this switch is related to increased
> Why did birds "revert"
> back to the bird hipped form?
They didn't revert, they evolved a similar, but different, structure
Note, some "lizard-hipped" dinosaurs are now known to have had a true
The peace of God be with you.